Improved furnace for heating and annealing steel ingots



. to the several compartments.

UNrrED STATES PATENT OFFICE.

sILAs o. sALrsBUnY, or NEW YORK, N. Y.

IMPROVED FURNACE FOR HEATING AND ANNEALING STEEL INGOTS, &c.

Specification forming part of Letters Patent No. 88,084, dated March 23, 1869.

To all whom t may concern.-

Be it known that I, SrLAs C. SALrsBURY, of the city of New York, in the county of New York and 'State of New York, have invented certain new and useful Improvements in Furnaces for Preparing Ingots of Steel, and applicable to furnaces for annealing iron and glass; and I do hereby declare that the following is a full, clear,A and exact description thereof and of their mode or manner of operation, reference being had to the accompanying drawings, and to the letters of reference marked thereon, and making a part of this specification.

The object of my invention is, more particularly, the production and arrangement of a furnace for heating ingots of steel, preparatory to rolling or hammering for refining purposes, whereby such ingots can be heated to the degree of heat required or desired without coming in contact with the coal or the imme` diate products of the combustion of the coal,

and in which the heating or preparing cham-- ber can be under such control and regulation as to insure the most perfect success to the treatment required.

Figure l is a general perspective view of the entire furnace, and showing the openings Fig. 2 is a vertical section of Fig. 1, showing part of the lire or preparing chamber in perspective. Fig. 3 is a bottom view of the grate and under side of the furnace; Fig. 4, a detached view of a section of the outer lining of hre-chamber.

The base-plate A and grate B are made of cast-iron, the latter formed with numerous separate openings a, for taking in air, substantially as shown in Fig. 3, so that the air will be supplied to the under side of the fire in separate divided currents, and to all parts substantially alike.

For the purpose of receiving and supporting the outer and inner walls or linings of the furnace, I prefer to cast or form the base-plate with two annular concentric recesses, which may be either sunken or have flan ged edges, and which are separate from each other a littie distance, about half an inch to an inch, in which space is a series of holes for the free admission of air, for the purposes hereafter mentioned.

Resting in the outer recess referred to, and

extending entirely around the fire-chamber,

and projecting upward about as far as the perpendicular sides ofthe fire-chamber, is a castiron plate, C, from half an inch to au inch in thickness, on the inner sides of which, or made a part of it, and placed at suitable intervalssay, every two or three inches-is a series of pipes or half-round tubes, b, which are open at the bottom, to freely take in air, and closed a't the top, to prevent the air passing through them, but having, along their inner sides, a

series of vertical holes, o, to allow the air to Ypass out horizontally. A section of one of such tubes is shown in Fig. 2, and a detached portion of the cast plate C and its tube bin Fi 0. 5. y

z{Vithin such cast-iron plate, and in contact with the inner sides of the tubes b, and resting in the inner recess, before mentioned, of the base-plate, is placed a ring of fire-brick, D, which also extends entirely around and forms the inside wall of the tire-chamber E, and through which are also made perforations cl, corresponding in position with the holes c in the tubes b.

By means of such arrangement of air-tubes b, perforated as described, and the perforated fire-brick D, air is constantly supplied to the fire-chamber E in divided jets on every side of the burning fuel, and at the top thereof, and at different places below. Large quantities of air are thereby not only continually supplied to such chamber, but it is presented to and distributed through every part of the burning mass, and as such air becomes highly heated before it reaches the fire-chamber, by passing through the tubes b and the perforated fire-brick, such chamber is, in fact, continually supplied with a hot blast, and to assist in so heating the air the tubes b may be filled with iine gauze asbestus cloth, which can be kept constantly very hot without being destroyed.

Atmospheric air is forced, by means of blastengines, through the receiving-pipe E into the sections f fand into the annular chamber D, and thence, through the passages 1 2 3, to the furnace. As such air is thus supplied to the furnace through many passages or conveying-tubes,1 2 3, etc., it is divided into numerous and comparatively small currents instead of being delivered into the furnace in comparatively large quantities or currents, and it is also delivered into the furnace, on each side thereof, instead of at but two or three ora fewplaces, as bytheordinarytuyeres,

and in passing through the highly-heated furnace-lining, I am enabled to heat the blastl at a very small expense comparatively, and also to heat it to a much higher temperature than is possible by the ordinary methods, and by delivering such blast in the furnace at a great number of dierent places instead of at but two or three, as when tuyeres are used, I thereby increase the means of producing and secure a more perfect combustion, effecting the consumption of the powerful gases as they separate from the coal, and thus more perfectly deoxidizin g the ores, and also more completely and uniformly decompose the matter used for iluxing, and thus obtain a much better iiux, and the iron is also rendered so fluid or thin in quality as to vinsure its rapid and free access to the receiving-pan or hearth c below.

In the air-chamber I), in range, or substantially so, with the upper tier of hollow brick, or with the upper air-tube, l, I place a coil of steam-pipe, d, which is perforated, opposite such tube l, with small tubes, or tted with 'small jets, into which steam passes under high pressure, and is supplied to the furnace, in connection with the hot-blast, through the same passages l 2 3. As such steam passes through the fire-bricks and comes in contact with the red-hot iron it becomes decomposed, forming oxygen and hydrogen, the former of which unites with the carbon, and the latter,

by reason of its greater affinity for the sulphun in the coal, unites with such sulphur, and in, its upward passage consumes it.. By this` means the sulphur is prevented from uniting with the iron, thereby producing a better quality of iron, and the iron is also, to a great degree, if not wholly, decarbonized at the same time it is smelted.

By such arrangement and construction of furnace the ordinary hot-air furnaces can be dispensed with and less powerful and costly blast-engines are required, and the parts of the furnace most liable to be destroyed by the great heat are rendered more durable, and also the quality of the iron produced is greatly improved.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. Constructing the lower part of the furnace of perforated or hollow brick, or brick having air passages or pipes l Z 3 extend ing through them, substantially as and for the purposes set forth.

2. In combination with the perforated brick, as described in the foregoing claim, the arrangement of the air-chamberl), substantially as and for the purposes set forth.

3. The combination, with the perforated brick, as and for the purposes described, of the steam-pipe d, substantially as and for the purposes set forth.

4. Supplying the hot-air blast by means of the passages l 2 3, or any equivalent means, in numerous small currents or blasts, on every side of and at diiferent points in the lower sec-v tion of the furnace, for the purposes set forth.

5. A blast or similar furnace constructed and arranged substantially as and for the purposes set forth.

SILAS C. SALISB URY.

Witnesses:

S. D. LAW, FRED. B. SEARS. 

